People who work for the public sector - doctors, nurses, teachers, politicians, refuse collectors, lab technicians, porters, council employees, etc. etc., are taxpayers too.
People who pay into a private pension contribute a very significant - and disproportionate - amount to the high salaries of pension fund managers, similarly for the high salaries of CEOs of water companies, energy companies, transport companies, etc. etc. These are hardly non-essential things that we can choose to do without and yet we have no control over what these people are paid.
It seems to me the BBC can't win. If it tries to meet its public service remit of educating and informing as well as entertaining it is criticised for not receiving high enough viewing figures because it produces programmes that are too "worthy" or "niche". It is then told it needs to compete with the commercial channels, which means producing the sort of programmes that have mass appeal, employing people like Graham Norton, or producing dramas with "big names" in them. Presenters and actors, are, in general, no more altruistic than any other working person and are not willing to accept a significantly lower fee from the BBC when a commercial channel is offering a much higher sum.